Electric stop mechanism for knitting machines and the like



J. WACHSMAN Dec. 9, 1930.

1,784,560 ELECTRIC STOP MECHANISM FOR KNITTING MACHINES AND THE LIKE Filed Jan. 15, 1929 R w m lNV NTOP Jawzlkamwz v BY {AA/VA ATTORNEY Patented Dec. 9, 193 0 JACOB WACHSHAN, OF BROCKLYN, YORK ELECTRIC STOP MECHANISM FOR KNITTING ES AND THE LIKE Application filed January 15, 1929. Serial No. 832,644.

My invention relates to devices used to actuate or control the stop mechanism of kmtting machines and other similar apparatus upon breaking or knotting of'the thread.

Primarily, the invention has for its object to provide mechanism which will act qb and surely so as to stop the machine etore damage to the cloth occurs.

Further, the invention has for an object to provide means whereby the electric circuits to the stop actuating magnet of the knitting machine will be closed by clean contacts of metal which will not readily corrode, thereby insuring operation of the device at all times 1 under all conditions.

Further, it is an object of the invention to provide a primary circuit closer device controlled by the thread (which, if thb thread breaks or hlOllS, will close the circuit) which 249 device is of such construction that it cannot be improperly threaded, or in other-words, it is an object of my invention to provide such a device with means whereby the new loop of the thread must always be placed in proper position on the control lever before the circuit to the stopping machine will be opened to permit the machine to begin work again.

Further, it is an object to provide reliable stop mechanism for use on machines using to light silk threads.

Further, the invention has for its object to provide a circuit closer having a duplex set of closing contacts, one including a gravity operated lever which, when the thread breaks,

will fall and close the circuit, andthe other including a spring-held lever which operates by a pull on the thread to close the circuit, the two levers being cooperatively associated.

Another object-is to provide an improved tension adjusting device for the spring that holds the spring-held lever in the circuit open position so that danger or' twisting and breaking the coil spring employed may be avoided.

an needles so as to insure-an instantaneous stopuickly Further, the invention has for its object to ping of the machine upon the breaking or knotting of the thread.

Again, it is an object to provide an auxiliary device to close the circuit if the thread breaks adjacent the bobbin, such device having combined with it an adjustable thread tensioning. means (for silk machines especially) to keepthe thread taut and eliminate knotting due to slack, as well as to hold the thread sufficiently taut under normal work-* ing conditions so as to prevent the primary circuit closer from operating in the event that the thread tends to slack due to normal fluctuations caused by the knitting machine.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends, my invention consists in the novel features of construction and in the combination, connection and arrangement of parts, hereinafter more fully described and then pointed out in the appended claims.

in the drags:

hi 1 is a diagraatic elevation showing my invention in use.

Figure 2 is a side elevation with the cover plate removed, of the primary circuit closer unit, the parts being shown in full lines in the position they assume when new thread is in place, other positions, hereinafter referred to, eing indicated in dotted lines.

Till

Fire 3 isa vertical longitudinal section taken substantially on the line 8-3 of Figure 6.

Figure 4 is a detail perspective view of the spring-held lever. 1

Figure 5 is a detail perspective view of the gravity operated lever.

igure 6 is a top pl view of the primary circuit closer unit.

Figure 7 is a central vertical longitudinal section of the second circuit closer unit.

Figure 8 is a front elevation of the same.

the wing in which like numerals of reference indicate like parts in all of the figures, 1 represents a. bobbin stand which may be of any usual construction and con tains the main shaft 2 that carries the upper ulus 3 as shown. To 1 the annulus 3 is secured the pnmar'y c'ircuitcloser 6 constituting one of the essential improvements of this invention. cludes a casing provided with a top horizontal ear 7 by means of which it can be secured to a support such as the element 3 for instance and there is also provided a lower ear 8 by which the device can be mounted. When mounted by the lower ear 8 it is mounted as indicated in Figures 1 and 2 of the drawing. When the primary circuit closer unit is mounted as shown in Figures 1 and 2 the upper annulus 3 is preferably provided with holes 4 for convenience in obtaining access to the tensioning screw 31 herein again referred to. It will be observed that the casing of the primary circuit closer is closed except for an opening 9 in the front wall through which operating levers project. The casing is provided with a removable cover 11 and carries a pivot bolt 10 which also serves to secure the cover in place.

An electric terminal 12 is supported on the casing and insulated from the same and carries a double contact finger leaf spring 13. This spring consists of a leaf slit lengthwise and bent to form two contact fingers l4 and 15 respectively. The finger 14 extends forward of the finger 15 as best shown in Figures 2 and 3 of the drawing.

Pivoted on the bolt 10 is what I hereinafter term a spring-held lever which is shown in detail in Figure 4 and comprises the parallel arms 16 connected at the front by a downwardly projecting loop 18 and having fulcrum ears or hearing loops 19 as shown. Projecting backwar'dly from the ears 19 the lever is bent to comprise a counterbalancing loop 21 and a tension spring attaching eye 20, the latter also serving as a contact heel to engage with the spring finger 14 at times as will hereinafter more clearly appear.

22 is the bearing body of the gravity actuated lever, the body 22 being fulcrumed on the pivot bolt 10 and carries the contact finger 23 which cooperates with the spring finger 15 to close the circuit at times. I

The gravity actuated lever also includes the forwardly projecting actuated part 24 that projects through the opening 9, (as does also the porcelain cover portion 17 of the parallel arms 16 of the spring held lever) and projects between the parallel arms 16 as best shown in, Figures 2, 3 and 6 of the drawing.

The projecting portion 24 of the gravity actuated lever may be made of steel or other suitable material and is secured in the body 22 by looping it therein as indicated at 25 in the drawing.

- The lever portion 24 is bent to provide a thread holding loop 26, a lifting incline 27 and a front finger 28, the latter projecting beyond the loop 18 and adapted to rest in that loop at times as will be more clear later.

29 is a coiled tension spring, one end of The primary circuit closer in-' which is hooked in the eye 20 and the other end is connected to an adjusting bar 30 which slides up and down in the housing6 and is adjusted by means of an adjusting screw 31 that can be operated by a screw driver through the hole 4 when it is necessary to adjust the tension of the spring.

As far as described it will be seen that when the parts are positioned as shown in ,full lines cuit between the contact 15 and the contact finger 23 the thread 48 is passed under the finger 28 and over the parallel arms 16, thus lifting the gravity actuated lever toward the position shown in dotted lines in Figure 2 until the thread is in place when that lever will drop to the position shown in full lines in Figure 3. When the parts are in this position the circuit will be open between both contact fingers 14 and 15 and the two levers, Figure 3 being the normal operatingposition of these parts. Should, however, the thread break there will be nothing to sustain the gravity actuated lever in the full line position shown in Figure 3 with the result that it will fall to the position shown in full lines in Figure 2, close the circuit at 15 and energize the stop magnet 58 to operate the stopping lever 57, through the circuit connections 66, 61 and battery 59.

If the thread is in the position shown in Figures 1 and 3 and a knot comes along, since the knot cannot pass the eye 47, therefore the spring-held lever will be moved from the full line position shown in Figure 2 to the dotted line position shown in that figure, thereby closing the circuit between the heel 20 and the contact finger 14, as well as close the circuit between the contact finger 23 and the spring contact finger 15 and allowing the thread to slip ofli ofthe spring-held lever and thereby cause its release, the knitting machine being stopped, however, by the electric action before damage to the cloth or thread can occur.

In order more fully to protect" the cloth against damage as well as to assist the primary circuit closer in performing its function properly under all conditions and especially when light silk thread is being used, I provide a second circuit closer 32 which is mounted on the intermediate support 5 adjacent to the bobbin 49. This second circuit closer, which is illustrated in detail in bushed thread-passing eye 47 provided in the base of the support 33 as hest shown in Figure 7.

There-is also provided as a part of thesecond circuit closer a contact box 35 in which is tulcrumed a gravity actuated lever 39,-

the latterhaving a contact loop arm to engage with the springy fixed contact 38 that is mounted in. the contact box and suitably insulated therefrom as at 37. The contact These eyes are adapted to be projected forwardly through openings 42 in the front of the support and held in that position by the thread when the machine is operating under normal working conditions.

In addition to providing the lower means of mounting the support 33 it may also be provided with an upper mounting car 43 as it may sometimes be found more convenient to mount by means of the ear 43 than by the base of the support.

lllounted on the front of the support 33 is and adjustable thread tensioning device. 44 of the construction usually found on sewing machines and the like. As the construction of this device is well hown a detail description thereol is thought to be unnecessary.

' The gravity actuated lever 39 is provided with overbalancing arms 45 and 46 whereby, when the thread is not passing throu the eyes, the lever will be moved back by gravity to the full line position shown in Figure 7 and thereby close the electric circuit between the elements 40 and 38 to operate the magnet 58 via the circuit wires 62, t3 andcbatt ery 59 as indicated in Figure 1.

50 designates a thread guide and part of a.- tensioning device, one part of which is constituted by an arm 54 coiled around a drum 52 as a spring 53, and having its other end provided with an eye 55 through which the thread may be passed. This arm or lever 54 has its drum 52 mounted on a suitable support 51 sustained on the intermediate support 5 and cooperates with a tiered contact 56 mounted on the shaft 2 when. the thread breaksin passing from the bobbin stand to.

the machines needles.

llt will be seen, by reference to Fire 1,

- that the springy arm 54 serves as a slack -magnet 58 via wires t4 and and battery 59 and operate the lever 57 oi? the stop mechanism to stop the machine. J

it will be seen from th foregoing that the device, which, in cooperation with the adjustable tension 44, enables just the right amount of tension to be put upon the thread 48 to keep it) cu1t closer from forcing the thread down bei the gravity actuated lever of the primary cirtween the parallel arms 16 thereof.

- By providing the several places for closing the circuit to stop mechanisms magnet, ll insure an instantaneous stopping of the machine regar'dless of whether the thread breaks slack take-up arm 54 constitutes a tensioning close to the bobbin or at some point in its travel between the bobbin and the needles of the knitting machine.

- Furthermore adequate provision is made in case the thread knots to close the circuit and stop the machine before the; knotted portion of the thread can reach the clot-h and spoil it. This also gives ample time, in case a thread breaks, for the attendant to tie the thread again and if the bobbin gives out to put a new bobbin in place and tie its thread onto the end of the preceding thread before the end of the preceding thread can reach the cloth.

ll might also call attention to the fact that the electrical contacts of the primary circuit closer and those of the secondary circuit closer are what may be termed wiping contacts, i. e., they rub on one another and thus keep the contacting surfaces clean, thereby insuring good electrical connections at all times.

From the foregoing description, taken in connection with the accompanying drawing, it is thought that the complete construction, operation and advantages of my invention will be clear to those shlled in the art to which it appertains.

What I claim is: a

1. ln stop mechanism under control of a travelling thread the combination with an electric circuit including an operating magnet and a source of electric energy-to actuate the stop device of a machine; a bobbin stand, a primary circuit closer pnit mounted on said stand and including circuit closing contacts normally held open by the unbroken thread and including means to close the contacts upon breaking or knotting of the thread, a sec ond circuit closer unit located between said primary unit and the bobbin and adjacent to the bobbin to close the circuit upon breaking of the thread adjacent the bobbin and upon passage of the end of thethread from the bobbin.

2. ln stop mechanism under control of a travelling thread the combition with an electric circuit including an operating magnet and a source of electric energy to actuate the stop device of a machine; a bobbin stand, a primary circuit closer unit mounted on said stand and including circuit closing contacts normally held open by the unbroken thread and including means to close the contacts upon breaking or lmotting of the thread, a

second circuit closer unitlocated betweenaid w and a source of electric energy to actuate the comprising a hous1ng,a fixed leaf spring concuit u on breaking of the thread.

primary unit and the bobbin and adjacent to associated with the thread between the bobbin the bobbin to close the circuit upon breaking and said primarycircuit closer unit and com of the thread adjacent the bobbin and upon prising a support, a tension adjusting depassage of the end of the thread from the bobvice on the support, said support having at bin, and a third circuit closer unit mounted least one opening, a, lever with at least one on the bobbin stand and associated with the thread-passing eye associated with said open- 'thread where it passes from the bobbin stand ing and adapted to move back through said in order to close the circuit upon breakage of opening by gravity, said last named lever the thread on leaving the stand. having a contact member, and a stationary 3. In stop mechanism under control of a contact member associated with said levers travelling thread the combination with an contact member; and mounted on said supelectric circuit including an operating magnet port for the purposes specified, all being and asource of electric energy to actuate the arranged whereby the adjustable tensioning stop device of a machine; a bobbin stand, a and circuit closer unit will maintain suificient primary circuit closer unit mounted on said tension normally on the thread to hold the stand and including circuit closing contacts primary circuit closer open. normally held open by the unbroken thread and including means to close the contacts of a travelling thread, a circuit closer unit upon breaking or knotting of the thread, an comprising a housing, a fixed leaf spring conadjustable tensioning meansassociated with tact member insulated from and mounted the thread before it passes to said circuit in said housing, a circuit terminal therefor, closer unit angla yieldable tensioning means said spring-having two contact arms, a springassociated with the thread after it passes said held lever fulcrumed in said housing and circuit closer unit. 1 comprising two substantially parallel arms 4. In stop mechanism under control of :1 extending to the outside of said housing and travelling thread the combination with an having a contact heel to engage one of the. electric circuit including an operating magnet arms of said leaf spring at times, an adj ustand a source of electric energy to actuate the able spring tension for said spring-held lever, stop device of a machine; a bobbin stand, a a gravity actuated lever also fulcrumed in primary circuit closer unit mounted on said said housing and having a contact arm ,to stand and including circuit closing contacts engage at times with the other, leaf spring normally held open by the'unbroken thread arm and having an operating arm extending and including means to close the,.contacts to the outside of said housing in association upon breaking or knotting of the thread, and with the parallel arms of said spring-held a combined yieldable tensioning means and lever, said operating arm extending between circuit closer unit associated with the thread said parallel arms, said parallel arms having after'it leaves said primary circuit closer unit. a stop loop with which said operating arm 5. In stop mechanism under control of a may engage when no thread is present. travelling thread the combination with an 8. In stop mechanism under the control electric circuit including an operating magnet of a travelling thread, a circuit closer unit stop device of a machine; a bobbin stand a tact member insulated from and mounted primary circuit closer unit mounted on said in said housmg, a circuit terminal therefor, stand and including circuit closing contacts said spring having two contact arms,a springnormally held open by the unbroken thread held lever fulcrumed in said housing and and including means to closethe contacts upon' comprising two substantially parallel, arms breaking or knotting of the thread, an adextending to the outside of said housing and justable tensioning means associated with the having a contact heel to engage one of the thread before it passes to said circuit closer arms of said leaf spring at times, an adjustunit and a yieldable tensioning means assoable spring tension for said spring-held lever, ciated with the thread after it passes said a gravity actuated lever also fulcrumed in circuit closer unit, and means adjacent said said housing and having acontact arm to adjustable tensioning means to close the cir-r engage at times with the other leaf spring arm and having an operating arm extending 6. n stop mechanism under control of a to the outside of said housing in association travelling thread where-in is provided an elecwith the parallel arms of said spring-held tric circuit including an operating magnet lever, said operating arm extending between and a source of electric energy to actuate the said parallel arms, said parallel arms having stop device of a machine, a bobbin stand, a a stop loop with which said operating arm primary circuit closer unlt mounted onsaid may engage when no thread is present, said stand and including circuit closing contacts operating arm having a finger end projectednormally held'open by the unbroken thread beyond said parallel arms.

and including means to close the contacts 9. In stop mechanism for knittlngmachlnes upon breaking or knotting of the thread, an and the l ke, a c1rcu1t closer comprising a adjustable tensioning and circuit closer unit plate having at least one opemng and hair.

7. In stop mechanism under the control ing a forwardly pro ecting portion at the bottom with a thread-passing eye and having a rearwardly projecting portion at the top for mounting purposes, a box having its front open and secured to the back of said plate, the plate serving as a closure for the opening of said box, a lever having bearing portions and a heel, said box having edge notches constituting bearings for said bearing portions, the heel of said lever being located within said box, said lever having at least one thread-passing eye adapted to be projected through said opening of said plate, an insulated contact spring within said box cooperating with said heel, said lever being so weighted that it will fall by gravity backwards to withdraw its thread-passing'eye through said opening from the front to the back of said plate substantially as shown and described.

10. In stop "mechanism, a circuit closer comprising a plate having its upper end bent rearwardly to provide a securing ear and having its lower end extending forwardly-and, rearwardly, the rearwardly extending Rortion serving as a securing meansand the forwardly extending portion having an eye I for the passage of a thread, said plate having at least one opening in its wall, a box having one open ,side, said box being secured to the back of said plate, said plate serving as aclosure for the box, a contact finger mounted in and insulated from the box, a wire lever having bearing portions and a loop or heel, the later being located in the box, sa'id box having'bearing notches in its front edge for said bearing portions, said wire lever extending upwardly above said box and having at least one thread-passing 0 eye associated with said opening in said plate and counterbalanced to move by gravity toward the back of said plate to bring its heel. into contact with said insulated contact, said wire lever adapted to be moved to project its a thread-passing eye through said opening in said plate whereby a thread may be assed along the front of said plate throng said thread-passing eye for the purposes described.

JACOB WACHSM N. 

